Hi guys, i've made a custom screen, that is showing a value in a field in a drop down field in the grid, which is working just fine - if the customer then choses the "Group by" option on the column, it groups the values based on the id of the underlying field, and not by the friendly value ( of the dropdown array):

How can i get it to use a friendly value for grouping, instead of the number? Same goes for sorting, as it will sort based on the number and not the friendly value.
Thanks in advance.